Futher Modifications in Darshan's Code

[MananTheCoder]

1. The question number part in the nameOfFile variable in evaluate_user method is defined as nameAsList[0][0] + "_" + nameAsList[1][0] + "_" + **question[-1]** + ".cpp". This'll pose issues if Question No. is > 9 ie there are > 9 Questions.
   Let's make it generic to read the numeric characters at the last of string for Question No.
2. Incentivising O(n) runtime over O(n^2) etc.
3. remove the temp_executable file after the code run is complete.
   Likewise, in java files, cleanup the class files for each user after the run.
   @Darshan-Padia